Chapter 2 Flashcards
genetic information; what your genes let you express
genotype
expressed, directly observable, characteristics
phenotype
What are the three components of the nucleus’s genetic blueprint?
chromosomes, genes, DNA
store and transmit genetic information; within cell nucleus
chromosomes
segments of DNA along the length of the chromosome
genes
directly affect our body’s characteristics
protein-coding genes
modify the instructions given by protein coding genes
regulator genes
sex cells (sperm and ovum); contain 23 chromosomes
gametes
union of sperm and ovum (conception)
zygote
result when a zygote separates into two clusters of cells that develop into two individuals; individuals have the same genetic makeup
monozygotic (identical) twins
result from the release of two ova; individuals genetically no more alike than ordinary siblings
dizygotic (fraternal) twins
versions of genes (heterozygous or homozygous)
alleles
expressive dominant or recessive trait
homozygous
expressive dominant trait only
heterozygous
both alleles are expressed in the phenotype resulting in a combined trait that is intermediate between the two (e.g., sickle cell trait)
incomplete-dominance pattern